Being able to choose between 3 intelligent heating modes allows you full control over your pool temperature. In ECO mode, the pool heater only uses 50% of the available energy, saving you money in the long run. It also is the quietest mode at as little as 25 decibels. That’s as quiet as the inside of a library – not bad for an efficient pool heat pump! The Smart mode operates between 50-100% and the Boost mode allows you to run a quick cycle at full power, enabling the Zodiac ZS500 MD8 to heat up your at its quickest rate.